gold
Enable an AI agent to recognise gold as a colour quality, assess whether an observed or proposed appearance meets its intended gold reference, and choose justified matching or reproduction actions.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
Researched by: Codex + Grok
Purpose and description
Enable an AI agent to recognise gold as a colour quality, assess whether an observed or proposed appearance meets its intended gold reference, and choose justified matching or reproduction actions.
Gold is the monoisotopic chemical element Au (atomic number 79), a dense, highly ductile group-11 noble metal that occurs native and in tellurides and is specified, hallmarked, and priced by millesimal mass fraction of elemental gold rather than by colour or alloy family.
It can be Classify a candidate as gold, outside the selected gold definition or ambiguous, with the reference and conditions recorded.; Compare a candidate with an approved gold target and identify whether disagreement concerns colour, reflective appearance or both.; Request additional lighting, angle or calibrated capture observations when a single image cannot settle the match.; Specify a gold appearance for a target medium using an explicit reference and any required reflective effects.; Approve or reject a proposed gold substitute within recorded tolerances and decision authority.; Detect a change from an earlier accepted gold appearance without inferring its physical cause from colour alone..
Distinguishing features
Test whether 'gold' describes an appearance or a material claim; a colour observation alone does not establish gold content.
Compare the candidate with the task's gold reference and nearby yellow, ochre, orange and brown references under the same conditions; record ambiguous membership rather than impose an unsupported universal boundary.
Determine whether acceptance depends on a flat colour match or also on changing highlights and reflections when the surface or viewpoint moves.
Check whether 'gold' names a particular palette entry or a broader appearance family before treating two identically labelled samples as equivalent.
Separate a surface intended to be gold from a surface that merely appears golden under coloured illumination by checking additional lighting or capture evidence.
Scope
+ Gold as a named colour quality attached to a surface, image region or design specification.
+ The reference, naming convention and context that establish what counts as gold for a particular task.
+ Measured or encoded colour and the conditions needed to interpret it.
+ Whether the intended gold appearance includes metallic reflection, sparkle or directional variation.
+ Acceptance of gold colour matches and permitted substitutions across media.
- Gold as a chemical element, mineral, alloy or commodity.
- Purity, karat rating, authenticity and valuation of gold-bearing objects.
- Manufacture, composition and safety of pigments, coatings, foils and plating.
- The geometry, ownership and function of objects carrying gold colour.
- Award ranks, heraldic rules and cultural symbolism associated with gold.
Characteristics
- Gold designation basis
- named palette entry | physical reference | contextual colour judgement | unspecified Determines whether recognition depends on an exact specification or an interpreted colour family.
- Gold reference
- Link to an identified swatch, palette entry, approved sample or appearance specification, with version Gives matching decisions an explicit target instead of assuming every use of 'gold' means the same appearance.
- Colour coordinates
- Coordinates with named colour space, encoding and applicable profile or reference white Supports reproducible comparison of the colour component of a gold appearance.
- Gold appearance requirement
- flat colour sufficient | metallic appearance required | sparkle required | combined requirements | unresolved Prevents approval of a flat swatch when the task requires a reflective gold effect.
- Angular appearance variation
- Colour or luminance observations indexed by illumination and viewing angles in degrees Records whether a proposed metallic gold remains acceptable across relevant viewpoints.
- Observation conditions
- Linked illuminant, viewing geometry, surround, instrument or image capture record Allows an agent to distinguish a gold mismatch from a change in how the sample was observed.
- Difference from approved gold
- Named colour-difference metric and value, with comparison conditions and separately assessed appearance effects Supports task-specific acceptance without treating one numerical colour difference as a complete metallic appearance judgement.
- Gold match status
- unassessed | accepted for stated conditions | rejected | ambiguous | additional observation required Controls whether an agent may reuse, substitute or request further evaluation of the candidate.
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.gold-attribute
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 5 bundles · 9 layers · 16 findings · 24 questions.
Gold identity and boundaries Establish which colour meaning of gold applies and how a candidate is distinguished from neighbouring colours and material claims.
An agent must resolve what 'gold' means before interpreting measurements or choosing an appearance.
Gold designation
Identify the naming authority and intended breadth of the gold designation.
Operative gold reference
Record the reference that governs this use of gold and whether it specifies one colour or a permitted family.
- Does gold mean a named palette entry, an approved physical sample or a contextual colour family in this task? definition
- Who supplied the gold designation, and which reference or version supports it? provenance
Neighbouring colours and materials
Keep gold colour membership distinct from adjacent colour labels and claims about substance.
Gold membership test
Record the comparison that justifies the gold label and any separate material assertion.
- Which reference comparison separates this candidate from yellow, ochre, orange, brown or another locally relevant neighbour? boundary
- Is 'gold' being asserted only of appearance, or is there a separate composition claim that must be routed to a material model? boundary
Gold colour target and observation Make the intended gold colour and evidence of its observed appearance comparable.
A colour name or an unqualified image cannot establish whether a specific gold target has been met.
Specified gold colour
Resolve the reference into an interpretable colour specification without inventing a universal gold coordinate.
Interpretable gold values
Record colour values with the information required to interpret their intended gold appearance.
- What coordinates or measured reference describe the intended gold, and in which colour space and profile? measurement
- Were these values supplied by the reference owner, measured from a swatch or estimated from an image? provenance
Observed gold colour
Bind observations to the conditions under which the candidate appeared gold.
Observation validity
Assess whether the evidence supports comparison with the gold target or requires another observation.
- Under which illumination, surround and viewing geometry was the candidate assessed against the gold reference? measurement
- Could coloured lighting, white balance, clipping or reflected surroundings account for the golden appearance, and what additional observation would resolve that? action
Metallic gold appearance Represent reflective effects when they form part of the required gold appearance.
A gold colour target may require more than a flat colour match; the model must make that requirement explicit.
Gold effect requirement
Determine which visible effects are necessary for this use of gold.
Required gold cues
Separate the required gold colour from optional or mandatory metallic, glossy and sparkling effects.
- Would a uniform matte sample matching the target colour satisfy the gold requirement? boundary
- Which reflective or sparkling effects must be present, and which approved sample demonstrates them? definition
Gold across viewpoints
Assess the required gold effect across relevant lighting and viewing positions.
Directional gold match
Record whether the candidate matches the intended gold appearance across the observation range required by its use.
- How do the candidate's gold colour, highlights and darker regions compare with the reference as illumination or viewing angle changes? measurement
- Which views must pass before the agent can accept the metallic gold appearance? action
Gold reproduction and acceptance Determine whether a gold appearance can be reproduced, substituted or retained for a specific use.
An agent needs explicit criteria for accepting gold across media and for responding when an accepted appearance changes.
Gold medium transfer
Resolve what must survive when gold moves between a reference, a display, a print or a physical finish.
Permitted gold approximation
Record the appearance requirements a target medium can satisfy and the compromises authorised for this use.
- Can the target medium reproduce the required gold colour and effects, or only an approximation of them? boundary
- Who may approve loss of metallic reflection, sparkle or colour fidelity, and what proof must they assess? action
Gold match decision
Evaluate initial and continuing conformity to the approved gold appearance.
Gold acceptance and reassessment
Record acceptance against declared criteria and trigger reassessment when the gold appearance no longer meets them.
- What colour tolerance and separate effect criteria determine whether this gold candidate passes under the required conditions? measurement
- If a previously accepted gold now differs from its reference, should the agent request a controlled remeasurement, propose a replacement or refer the underlying surface for investigation? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Kinds and varieties
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- native gold (nuggets, placer grains, and natural Au-Ag electrum)
- jewellery karat alloys (yellow, white, and rose/red, typically 9-22 karat)
- investment bullion (LBMA Good Delivery bars, kilobars, and bullion coins)
- high-purity refined gold (999.9‰ four-nines and 999.99‰ five-nines)
- coinage gold (historically 900 fine in the United States, 916.7 fine in sovereign-type coins)
- industrial and electronic gold (bonding wire, contacts, sputtering targets, and electroplate)
- dental gold alloys
- colloidal gold and gold leaf
- Which of these kinds and varieties hold for the sense of gold this model covers, and on what evidence? provenance
Identifiers and schemes
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Wikidata - Q897 - Item for the chemical element gold.
- IUPAC element symbol / atomic number - Au / 79 - Symbol from Latin aurum.
- CAS Registry Number - 7440-57-5 - Elemental gold; also used for powder, flake, leaf, and colloidal gold as listed synonyms.
- PubChem CID - 23985 - NCBI PubChem compound record.
- ChemSpider - 22421 - RSC ChemSpider identifier.
- InChIKey - PCHJSUWPFVWCPO-UHFFFAOYSA-N - IUPAC Standard InChIKey for Au.
- Harmonized System 2022 - 710812 - Unwrought non-monetary gold (Wikidata HS 2022). Heading 7108 covers gold more broadly.
- NCI Thesaurus - C2392 - NCI concept code for gold.
- Which of these identifiers and schemes hold for the sense of gold this model covers, and on what evidence? provenance
Standards and regulation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- LBMA Good Delivery Rules for Gold and Silver Bars - London Bullion Market Association (minimum 995.0‰ fine gold; 350-430 fine troy ounces; mandatory marks).
- LBMA Responsible Gold Guidance - London Bullion Market Association (mandatory for Good Delivery refiners; implements the OECD five-step due-diligence framework and Gold Supplement).
- OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas, Supplement on Gold - Organisation for Economic Co-operation and Development.
- ISO 9202, Jewellery and precious metals - Fineness of precious metal alloys - ISO/TC 174 (recommended millesimal grades; no minus tolerance).
- ISO 19376-1, Jewellery and precious metals - Vocabulary - Part 1: Precious metals and units - ISO/TC 174.
- ISO 24018:2020 chemical-composition grades for gold bars (995 / 999 / 999.5 / 999.9‰) - International Organization for Standardization.
- Convention on the Control and Marking of Articles of Precious Metals (Vienna, 15 November 1972) - Hallmarking Convention / Common Control Mark, depositary Sweden.
- Hallmarking Act 1973 - United Kingdom (millesimal marks 375, 585, 750, 916 in place of carat stamps).
- BIS gold jewellery hallmarking (14K585-24K, HUID) - Bureau of Indian Standards / Department of Consumer Affairs, India.
- National legal minima for calling an article "gold" (for example 10 karat in the United States; 9 carat / 375‰ in the United Kingdom and Canada).
- Which of these standards and regulation hold for the sense of gold this model covers, and on what evidence? provenance
Real-world use
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Cast and minted as wholesale Good Delivery bars (~12.5 kg) and as 1 kg and smaller investment bars and coins held in vaults, ETFs, and central-bank reserves.
- Fabricated into jewellery and watch cases, typically 9-22 karat alloys of gold with silver, copper, zinc, nickel, or palladium, then hallmarked.
- Deposited or drawn as corrosion-resistant electrical contacts and semiconductor bonding wire; this is the main industrial sink.
- Used in dental restorations as gold-based alloys.
- Applied as gold leaf, electroplate, and rolled-gold cladding on base-metal objects.
- Mined as native metal or tellurides, then recovered by cyanidation (industrial) or mercury amalgamation (artisanal), and refined by Miller chlorination and/or Wohlwill electrolysis.
- Historically coined as circulating money; most circulating gold coinage ended in the 1930s and the international gold standard was abandoned after 1971.
- Which of these real-world use hold for the sense of gold this model covers, and on what evidence? provenance
Typical measurements
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- standard atomic weight Ar(Au) - 196.966570(4) - 1 (relative to 12C; 197Au only)
- density (pure metal, ~20 °C) - 19.3 - g/cm³
- melting point - 1064.18 - °C
- millesimal fineness (jewellery to four-nines bullion) - 375-999.9 - ‰ by mass Au
- karatage (jewellery) - 9-24 - karat (parts Au in 24)
- Good Delivery bar fine-gold content - 350-430 - troy ounce (1 toz = 31.1034768 g)
- Mohs hardness (pure gold) - 2.5 - Mohs
- crustal abundance (order of magnitude) - ~0.005 - ppm by mass
- Which of these typical measurements hold for the sense of gold this model covers, and on what evidence? provenance
Failure modes and hazards
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- Cyanide leach solutions used to dissolve gold in mining and plating are acutely toxic if released or mishandled.
- Mercury amalgamation in artisanal mining poisons workers and sediments; gold dissolves in mercury without a chemical reaction.
- Tungsten cores (density ~19.25 g/cm³ versus gold 19.3 g/cm³) defeat shop-floor specific-gravity checks on counterfeit bars; ultrasonic, conductivity, or core assay is required.
- Gold-plated, rolled-gold, and gold-filled base metal is sold as solid gold; surface XRF or a hallmark does not prove the core.
- Trace iron in otherwise fine gold can make it brittle and unworkable in rolling or coining.
- Nickel in some white-gold alloys causes contact dermatitis.
- Pure and high-karat gold is very soft (Mohs ~2.5) and wears, dents, and scratches in use.
- Conflict, illegally mined, and recycled gold can enter refinery feed; LBMA/OECD due diligence exists because origin is otherwise lost at melt.
- Elemental gold is chemically inert in bulk; soluble gold salts, aurocyanide complexes, and aqua regia solutions are the chemical hazards, not the metal itself.
- Which of these failure modes and hazards hold for the sense of gold this model covers, and on what evidence? provenance
Regional variation
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- British English uses "carat" for gold purity; American English uses "karat" (both abbreviated K). The gemstone mass unit carat (ct = 200 mg) is a different quantity.
- United Kingdom and Canada treat 9 carat / 375‰ as gold and stamp millesimal fineness under hallmarking law; the United States sets 10 karat as the legal minimum, with 14 karat the usual retail grade.
- India's retail jewellery market is dominated by 22 karat (916‰), with compulsory BIS hallmark plus a unique HUID; 20 karat / 833‰ is used in parts of Asia.
- ISO 9202 lists 333‰ gold, which some jurisdictions do not allow to be sold as gold.
- Europe and other Hallmarking Convention parties use independent assay-office marks and the Common Control Mark; the United States relies mainly on maker's marks and karat stamps.
- London wholesale settlement requires ~400 oz Good Delivery bars at ≥995‰; Asian retail and Shanghai-type trade is built around 1 kg 999.9 bars, for which ISO 24018 fills a gap LBMA does not cover.
- Historic coin alloys differ: United States gold coin was 900 fine with copper; British/Australian sovereign-type gold was 916.7 fine, Australia often with silver rather than copper.
- Which of these regional variation hold for the sense of gold this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Reported by the breadth pass; each item needs checking against its source before it becomes normative.
- pyrite (fool's gold, FeS2) - Pyrite is brittle, forms cubes, and has density ~5 g/cm³ and a dark streak; gold is malleable, yellow-streaked, and ~19.3 g/cm³. Nitric acid does not dissolve gold (the acid test).
- chalcopyrite - Softer brassy sulphide that tarnishes and is not malleable; same density and acid-test separation as for pyrite.
- tungsten (Au-plated bar cores) - Density is almost identical (~19.25 vs 19.3 g/cm³), so hydrostatic weighing fails; ultrasound, electrical conductivity, XRF of a cut face, or fire assay of a drill core separates them.
- gold-plated or gold-filled brass/bronze - Surface colour and even a surface XRF reading can match gold; wear-through, density, a file-and-acid test, or fire assay of the core shows base metal.
- rolled gold / gold filled - A mechanically bonded gold-alloy skin on base metal, thicker than electroplate but not solid gold; cross-section or destructive assay, not the exterior colour, is the test.
- platinum - White, denser (~21.45 g/cm³), much higher melting point, and a different hallmark/XRF spectrum; not dissolved by the same aqua-regia conditions as readily as gold in workshop tests.
- sterling or fine silver (versus white gold) - Lower density (~10.5 g/cm³), different XRF/hallmark, and silver dissolves in nitric acid while gold does not.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of gold this model covers, and on what evidence? provenance
Sources
- Gold - Elemental identity, native occurrence and tellurides, acid test, cyanide and mercury behaviour, density match with tungsten, jewellery/investment/industry split of use, and post-1971 end of the gold standard.
- Gold | Au | CID 23985 - CAS 7440-57-5, PubChem CID 23985, Wikidata Q897, NCI Thesaurus C2392, InChIKey, and uses in jewellery, plating, currency, and dental restoration.
- gold (Q897) - Wikidata item Q897, CAS, ChemSpider 22421, InChIKey, 2022 Harmonized System code 710812, and the working description as element Au, Z = 79.
- Atomic Weight of Gold - CIAAW/IUPAC standard atomic weight Ar(Au) = 196.966570(4) from the single isotope 197Au, revised 2017.
- Purity of Gold - How purity is stated as percentage, millesimal fineness, or carat/karat; UK Hallmarking Act 1973 millesimal marks; fire assay as the historic referee method.
- Technical Specifications (Good Delivery Rules) - London Good Delivery gold bar: 350-430 fine troy ounces, minimum 995.0‰, required marks (serial, refiner stamp, fineness, date).
- About Good Delivery - LBMA as the body that sets wholesale bar standards and requires Responsible Gold Guidance of listed refiners.
- Gold Jewellery: Colour, Carat & Purity - Caratage versus millesimal fineness, troy ounce mass, US 10-karat legal minimum versus 14-karat popularity, and typical yellow/white alloy recipes.
- ISO 9202: Jewellery and precious metals - Fineness of precious metal alloys - ISO/TC 174 recommended jewellery finenesses for gold (including 375, 417, 585, 750, 916, 990, 999‰; 995‰ added in the 2026 edition) with no minus tolerance.
- ISO/DIS 19376-1, Jewellery and precious metals - Vocabulary - Part 1: Precious metals and units - ISO vocabulary: fine gold minimum 995‰, very high purity gold ≥999.99‰, troy ounce = 31.1034768 g, karat as parts in 24, and hallmarking as a national legal control system.
- Convention on the Control and Marking of Articles of Precious Metals (Vienna, 15 November 1972) - International hallmarking convention: gold as a precious metal, millesimal fineness, assay-office control, and the Common Control Mark (balance in a shield).
- Chemical properties of Gold Bullion guide - Density 19 300 kg/m³, melting point 1064.18 °C, Miller chlorination to ~99.5% and Wohlwill electrolysis to 99.99%, and Good Delivery minimum 99.5%.
- How to check purity of gold jewellery? Three signs to check for hallmarking - India BIS hallmarking: 14K585-24K permitted grades, 22K916 as the dominant jewellery mark, and unique HUID verification.
What the second pass must settle
- Which authoritative colour vocabularies and reference collections should govern gold membership beyond the registry's broad colour meaning?
- How should the model relate flat gold palette entries to metallic gold appearances without treating either as the universal definition?
- Which measurement protocols and acceptance criteria adequately describe directional and sparkling gold appearances in the intended application domains?
- Which boundaries between gold, yellow, ochre, bronze-like and copper-like appearances are supported by the relevant language and industry references?
- Which existing Vercy colour or appearance model already owns reusable comparison machinery, and should this entry specialise or link to it?